1. Field of the Invention
The invention relates to a data center that heat generated from an electronic device such as a server housed in a rack can be efficiently eliminated.
2. Related Art
In general, electronic devices such as a server, etc., are housed in racks with high density in multi-tiers, and are arranged in an air-conditioned room. Since heat is generated in the electronic device in accordance with power consumption, air-conditioned air (cool air) is generally supplied to the electronic device housed in the rack by a cooling system such as an air conditioner for removing the heat generated in the electronic device in order to eliminate an adverse effect due to the heat.
As shown in FIG. 7, a conventional data center is entirely configured by providing one or plural so-called modular data centers 70 in an air-conditioned room, the modular data center 70 in which rack rows 72 are formed in an air-conditioned room by horizontally aligning plural racks 71 housing electronic devices such as a server, etc., the rack rows 72 are arranged on a floor surface so that rear sides thereof face each other at a distance, the air-conditioned room is divided by providing a door 75 and a roof panel 74 in a horizontal direction of the face-to-face rack rows 72, i.e., on edge sides in a longitudinal direction so as to block a gap between the rack rows 72 for defining a hot zone between the back-to-back rack rows 72 on the rear sides thereof (for example, see JP-A 2006-526205). The door 75 is for entering inside the hot zone.
In addition, in a data center of JP-A 2006-526205 in which the modular data centers 70 is provided in the air-conditioned room, one of the racks 71 incorporates a cooling device (an air conditioner), and the air in the hot zone is cooled down and exhausted to the front side of the rack 71. In other words, in the modular data centers 70, air-conditioned air (cool air) is introduced from the front side of the rack 71 for removing the heat generated in the electronic device in the rack 71, the heat-absorbed air is exhausted to the hot zone from the rear side of the rack 71, and the air in the hot zone is cooled down by the cooling device and is exhausted to the front side of the rack 71.
A coolant supply and return pipe 76 for supplying a coolant such as water or chlorofluorocarbon, etc., is connected to the cooling device which is housed in the rack 71. Electric power is supplied to each electronic device in the rack 71 via a power supply line 77.
Thus, it is possible to effectively operate the cooling device by concentrating heat generated in the electronic device in a specific space (a hot zone). In other words, since it is not necessary to supply a low-temperature coolant equivalent to that for general air-conditioning facilities to the cooling device, it is possible to efficiently produce air-conditioned air (cool air) at a low cost without dehumidification.
However, in the above-mentioned data center, the heat generated in the electronic device is discharged into the air-conditioned room from an upper surface of the rack 71 (the rack row 72) and an upper surface of the roof panel 74 which may cause mixture of the heat with air-conditioned air (cool air) produced by the cooling device which is blown from the front side of the rack 71, and a result of the mixture, when it is not possible to sufficiently cool down the temperature of the air-conditioned air (cool air) introduced from the front side of the rack 71, it is necessary to further cool down the air-conditioned air beforehand by an air conditioner (an indoor air conditioner) other than the cooling device which is incorporated in the modular data center 70. Under these circumstances, energy consumed in the air conditioner (the indoor air conditioner) is wasted, thus, there is a problem from the viewpoint of energy saving.
Since there is a type of server which exhausts the air upwards, when such a server is housed in the rack 71, a large amount of heat is discharged from the upper surface of the rack 71 into the air-conditioned room, thus, the above-mentioned problem remarkably occurs.